In his speech at graduation, Moulton quoted the inscription on the inside of Dexter Gate: “Depart to serve better thy country and thy kind.”

“It’s about being there and doing your part, right alongside the next guy, and not letting someone else go in your place,” Moulton said at Memorial Church yesterday.

Moulton decided to join the Marines in 2001—before the Sept. 11 attacks—after long conversations with Plummer Professor of Christian Morals Peter J. Gomes.

In an interview yesterday, Gomes recalled telling Moulton: “Everyone has their vocation and a calling in life, and the great trick is to find out what it is and to pursue it.”

Gomes said he never explicitly advised Moulton to join the military, but urged Moulton “to fulfill what his own destiny and vision for service was.”

“I just really took seriously what Peter Gomes had to say about service,” Moulton said.

As an undergraduate, Moulton played the organ at Memorial Church and was an active member of the campus congregation.

“But I wasn’t like church geek, by any means,” he said.

Moulton was a physics concentrator in Currier House and rowed crew for two years.

When he returned from Iraq last September, Moulton said, he did not want to face the “predictable, repeated and unanswerable” questions from friends about Iraq. “I wanted a burger, a beer and a girlfriend, and was far more interested in hearing why Nomar was in a slump, how Martha had gone from the kitchen to the dog house, and whether or not Larry Summers was still president of Harvard.”

But in the last few days before he returns to the Middle East, Moulton, a native of Marblehead, Mass., is sharing his Iraq experiences with Harvard.

Moulton will again speak at Memorial Church on Sunday at 9:30 a.m. as part of the Faith and Life Forum.

—Staff writer Daniel J. Hemel can be reached at hemel@fas.harvard.edu.